On the small signal modeling of advanced microwave FETs: A comparative study

Although many successful techniques have been proposed in the last decades for extracting the small signal equivalent circuit for microwave transistors from scattering parameter measurements, small signal modeling is still object of intense research. Further improvement and development of the proposed methods are incessantly required to take into account the continuous and rapid evolution of the transistor technology. The purpose of this article is to facilitate the choice of the most appropriate strategy for each particular case. For that, we present a brief but thorough comparative study of analytical techniques developed for modeling different types of advanced microwave transistors: GaAs HEMTs, GaN HEMT's, and FinFETs. It will be shown that a crucial step for a successful modeling is to adapt accurately the small signal equivalent circuit topology under cold condition to each investigated technology. (c) 2008 Wiley Periodicals, Inc.